State continues ban on blue crab dredging, extends potting season

Winter dredging for blue crabs in the Chesapeake Bay is closed for the fifth year in a row as the Virginia Marine Resources Commission (VMRC) moved Monday to continue to protect and rebuild the stock of pregnant hibernating females.

To offset the impact on watermen, the commission also moved to extend the crab potting season by several weeks to Dec. 15, "which is going to be a boon to watermen," said VMRC spokesman John Bull.

The dredging ban was first instituted after a stock assessment found a 70 percent reduction in overall blue crab production in the bay — a percentage "approaching the danger level," said Bull.

Conservationists agree the fishery was at risk.

"The blue crab population for the better part of 15 years, prior to 2008, was showing signs of not being a healthy population," said Chris Moore, Hampton Roads scientist with the Chesapeake Bay Foundation. "The number of adult female crabs was down, exhibiting a number of warning signs. They had to come up with a more conservation-minded fishery management plan to rebuild. And help (watermen) have a more successfully fishery, as well."

After mating with males in the fall in the less-saline waters of the bay and its tributaries, female crabs naturally move to the saltier waters of the lower bay. There, they bury themselves in the sediment to over-winter.

Estimates are that about 95 percent of crabs harvested in the bay by winter dredging were females, Moore said.

In 2008, Virginia and neighboring Maryland joined in a management plan to eliminate winter dredging so pregnant hibernating female crabs that otherwise would be taken to market would be left alone to spawn in the spring and produce a new class.

"The crab population has responded beautifully," Bull said. "It has tripled over the last four years."

The commission voted Monday afternoon not only to extend that ban for one more year to allow the population to further rebuild, but to give researchers the chance to determine the impact of dredging on the crab population.

Dredging involves dragging a heavy metal scraper along the bottom of the bay to scoop up crabs in its wake. At other times of the year, and more popularly, watermen are permitted to harvest crabs using less invasive crab pots or cages or trotlines.

For its study, VMRC, along with scientists from the Virginia Institute of Marine Science in Gloucester Point will deploy four boats to dredge up crabs, catalog their size and gender and determine how many are damaged by the gear, Bull said. Then a larger scallop dredge will deploy behind the crab dredge to scoop up a bigger selection in order to determine the number of crabs damaged or crushed as the dredge gear passed.

"We're trying to determine what kind of waste of crabs is part and parcel to the dredge fishery in order to make sound decisions in future years over whether or not to allow dredge fishery to be reinstated," Bull said. "And, if so, under what conditions and with what limits."

The commission also voted to set new bushel limits as a conservation measure to offset any harvest increase that may come with extending the crab potting season. The new limits will depend on how many pots each license-holder is allowed to set, Bull said.